The issues I have or when I *think* I need the teeth:
Breaking up some ground for planting. Small garden area, seeding grass. Occasionally want to just tear up top couple inches of earth.
Grading an area with some grass. The little bit that grows on the "hump" in middle of dirt/gravel road for example the BB will just cut that off. But an area that is mostly covered with grass or weeds - even sparse - the BB tends to want to float over even shortly cut grass/weeds. For something like that, ripping it up some with the teeth, then going back over seems to work. Otherwise, regardless of angles I've tried, it doesn't seem to want to uproot any ground cover and just skims over. If sparse enough, going backwards and forward over same area several times might do it, might not.